Yes, caffeine, spicy foods, alcohol, and carbonated beverages are all on the list of things that *can* irritate the bladder (some sources also list citrus fruit, but that's more controversial).

That doesn't mean they all *will* irritate you if you have radiation cystitis — experiment a bit and see. I'm still ok with tea, but have to go easy on the alcohol and carbonated beverages (and not too close to bed). Orange juice is fine for me. Spicy food is usually ok, but sometimes irritates me if it's at the extreme limit (that's also the only time I notice my radiation proctitis, because it burns more on the way out than it did on the way in 😕).